1. Field of the Invention
The present invention generally relates to heat exchange devices, and more particularly relates to heat exchange devices used for heat exchange in products inside a flexible pouch.
2. Background Information
Many items, especially food items, are processed in bulk packages that are flexible plastic pouches. The product may be heated or cooked before it is added to the pouch, or it may also be cooked in the pouch. If the product is cooked before it is placed in the pouch, the hot product needs to be cooled quickly, and passed along to the next step in processing. If the product is added to the pouch while it is cool, heat must be transferred to the product in the pouch, and after the appropriate cooking process is finished, heat must be removed from the pouch and product for further processing.
Prior art devices, which are utilized to accomplish this heat transfer, require that the pouches be turned or otherwise reoriented during the heat transfer process. Sometimes this involves depositing the pouches in a container of water, which can either add or remove heat from the pouch.
What is needed in the industry is a heat transfer device that rapidly heats or cools products in a flexible pouch, and which handles the pouches on a continuous basis without the need to change the orientation of the pouch.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
These and other objects are accomplished by the device of the invention. In the device of the invention, flexible pouches containing a fluid or semi fluid product such as paint, chemicals, and a large variety of food products, are passed along a conveyor belt and pass under one or more pouch flexors. Although the invention can be utilized with any fluid or semi-fluid product in a flexible container, for convenience it will be described in relation to a food product in flexible pouches. In one configuration of the device, the pouch flexors are wheels or rollers. The rollers press down on the material in the flexible pouches and partially depress or constrict the pouch under the pouch flexor. The action of pressing down on the pouch causes movement and displacement of the material inside the pouch. This movement or displacement of material inside the pouch aids in the heat transfer from or to the material in the pouch. When a pouch is cooling by radiation, convection, and/or conduction, the outer layer tends to lose its heat more quickly, and the inner mass of food material retains its heat longer. By agitating, moving, and mixing the product, the warm areas of the material are mixed with the cooler surface zones to present more heated material at the surface for rapid heat transfer. The opposite happens when heat is being added to the pouch, resulting in enhanced heat transfer.
The pouch flexor is typically a wheel or roller, but can also be a fixed structure, such as a fin, wing, or ridge that is configured to press down on the pouch as the pouch passes by it. The device also includes a heat transfer medium for contacting the exterior of the pouch and for transferring heat to or from the product within the pouch. The heat transfer medium would typically be water, but other liquid materials could also be utilized, such as oil or other compounds and mixtures.
In the version of the invention using wheels, the wheels are typically mounted in a stationary position, and are configured to rotate as the pouch is transported past the wheels or rollers. The wheels or rollers may be above or below the pouch, which is typically carried on a conveyor belt. The pouch can be fully or partially submersed in water, and one strategy for use with the invention is to spray the heat transfer medium onto the pouches from above, below, or both directions.
Besides the wheel or fixed structure, a jet of air or gas can be utilized to compress and distort the material in the pouch, thereby mixing it.
The wheels or rollers may be configured to come into contact with a pouch sequentially, so that only one wheel or roller is in contact with the pouch at a time.
The invention also includes a device that is made up of one or more arrays of wheels or rollers, with conveyor belts for conveying a number of lines of pouches through the array of wheels or rollers. The arrays can be set up so that multiple conveyers travel through the arrays, with the wheels of the arrays contacting pouches on the conveyer belt while heat exchange medium contacts the pouches, by spray or immersion. The conveyer belt can be arranged in a spiral, with the pouches being carried through the spiral and being contacted by numerous wheel arrays and numerous sprayers of heat transfer liquid.
Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description wherein I have shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiment are to be regarded as illustrative in nature, and not as restrictive in nature.